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SparseArray vs HashMap
...pe.
There are some variants for different key/value types, even though not all of them are publicly available.
Benefits are:
Allocation-free
No boxing
Drawbacks:
Generally slower, not indicated for large collections
They won't work in a non-Android project
HashMap can be replaced by the fol...
LPCSTR, LPCTSTR and LPTSTR
...rase for simplicity, but as mentioned by lightness-races-in-orbit they are all pointers.
This is a great codeproject article describing C++ strings (see 2/3 the way down for a chart comparing the different types)
share
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C++, copy set to vector
...hold the input range.
std::back_inserter creates an output iterator that calls push_back on a container for each element, so each element is inserted into the container. Alternatively, you could have created a sufficient number of elements in the std::vector to hold the range being copied:
std::v...
In which order should floats be added to get the most precise result?
...estion I was asked at my recent interview and I want to know (I don't actually remember the theory of the numerical analysis, so please help me :)
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How to initialize log4j properly?
...
Log4j by default looks for a file called log4j.properties or log4j.xml on the classpath.
You can control which file it uses to initialize itself by setting system properties as described here (Look for the "Default Initialization Procedure" section).
For ex...
Create instance of generic type whose constructor requires a parameter?
...am Robinson
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What is the difference between print and puts?
... There is another thing ... extend the array class and override the to_s method. puts doesn't use the new to_s for an object of your new class while print does
– kapv89
Oct 28 '12 at 18:30
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Convert SQLITE SQL dump file to POSTGRESQL
...h a sequence to that column so that INSERTs with NULL ids will be automatically assigned the next available value. PostgreSQL will also not recognize AUTOINCREMENT commands, so these need to be removed.
You'll also want to check for datetime columns in the SQLite schema and change them to timestamp ...
Difference between numpy.array shape (R, 1) and (R,)
...
1. The meaning of shapes in NumPy
You write, "I know literally it's list of numbers and list of lists where all list contains only a number" but that's a bit of an unhelpful way to think about it.
The best way to think about NumPy arrays is that they consist of two parts, a data bu...
C++ auto keyword. Why is it magic?
From all the material I used to learn C++, auto has always been a weird storage duration specifier that didn't serve any purpose. But just recently, I encountered code that used it as a type name in and of itself. Out of curiosity I tried it, and it assumes the type of whatever I happen to assig...
